The present invention relates to portable cutting devices, such as a portable circular saw and particularly relates to, for example, a dust proof circular saw having a dust box for collecting chips.
Japanese Laid-Open Patent Publication No. 2000-37705 (hereinafter referred to as a Publication No. 705) and Japanese Laid-Open Patent Publication No. 2002-18811 (herein after referred to as a Publication No. 811) disclose a portable circular saw. The portable circular saw includes a circular saw main body with a motor for rotating a disc cutter blade, a rectangular base for supporting the circular saw main body and a fixed cover fixed to the circular saw main body so as to cover an outer peripheral surface of the disc cutter blade. A front end of the circular saw main body is pivotally attached to the base such that the pivotal angle of the circular saw main body with respect to the base can be adjusted in an up-down direction. In this way a projecting height of the disc cutter blade relative to the base can be adjusted and determined.
A dust cover is pivotally attached to a circular saw main body according to the Publication No. 705 so as to rotate about the same radial center as that of the disc cutter blade. The dust cover is positioned to cover a gap between the fixed cover and the base in the vicinity of the pivotal fulcrum of the circular saw main body. A distance between the fixed cover and the base varies when the circular saw main body base is vertically pivoted with respect to the dust cover. The dust cover rotates with respect to the fixed cover in accordance with the pivotal movement of the circular saw main body. In this way the dust cover is able to reliably cover the gap between the fixed cover and the base regardless of the pivotal angle of the circular saw main body. As a result, it is possible to prevent chips from blowing out of the gap between the fixed cover and the base.
A slide cover is attached at a front end of a fixed cover in a vertically slidable manner according to the Publication No. 881. A distance between the fixed cover and the base varies when the circular saw main body base is vertically pivoted with respect to the dust cover. The dust cover rotates with respect to the fixed cover. The slide cover is designed to cover the gap between the fixed cover and the base regardless of the vertical pivotal angle of the circular saw main body.
The vertical pivotal angle of the circular saw main body with respect to the base is adjusted before the circular saw main body is positioned. Further, the lateral tilting angle of the circular saw main body with respect to the base also could be adjusted before the circular saw main body is positioned. Thus, there is a need of a configuration that can efficiently prevent chips from being scattered not only if the vertical pivotal angle of the circular saw main body with respect to the base is adjusted but also even if, for example, the lateral tilting angle of the circular saw main body with respect to the base is adjusted.